<template>
  <div class="list" ref="wrapper">
    <div>
      <div class="area">
        <div class="title border-topbottom">当前城市</div>
        <div class="button-list">
          <div class="button-wrapper">
            <div class="button">{{currentCity}}</div>
          </div>
        </div>
      </div>
      <div class="area">
        <div class="title border-topbottom">热门城市</div>
        <div class="button-list">
          <div class="button-wrapper" @click="handleCityClick(item.name)" v-for="item of hot" :key="item.id">
            <div class="button">{{item.name}}</div>
          </div>
        </div>
      </div>
      <div class="area border-topbottom" v-for="(item,key) of cities" :key="key" :ref="elem =>elems[key] = elem">
        <div class="title border-topbottom">{{key}}</div>
        <div class="item-list">
          <div class="item border-bottom" v-for="innerItem of item" :key="innerItem.id" @click="handleCityClick(innerItem.name)">{{innerItem.name}}</div>
        </div>
      </div>
     </div>
  </div>
</template>

<script>
import { mapState, mapMutations, useStore } from 'vuex'
import { onMounted, watch, ref} from "vue";
import { useRoute, useRouter } from "vue-router";
import Bscroll from 'better-scroll'
export default{
  name: 'CityList',
  props: {
    hot: Array,
    cities: Object,
    letter: String
  },
  setup(props){
    const store = useStore()
    const router = useRouter()
    const currentCity = store.state.city
    const elems = ref({})
    let scroll = null
    const wrapper = ref(null)
    function handleCityClick(city){
      store.commit('changeCity',city)
      changeCity(city)
      router.push('/')
    }
    watch(()=>props.letter,(letter,preLetter)=>{
      if (letter && scroll) {
        const element = elems.value[letter]
        scroll.scrollToElement(element)
      }
    })
    onMounted(()=>{
      scroll = new Bscroll(wrapper.value, {
        click: true
      })
    })
    return {currentCity, handleCityClick,elems,wrapper}
  }
}
</script>

<style lang="stylus" scoped>
  .border-topbottom
    &:before
      border-color #ccc
    &:after
      border-color #ccc
  .border-bottom
    &:before
      border-color #ccc
  .list
    overflow hidden
    position absolute
    top 1.58rem
    left 0
    right 0
    bottom 0
    .title
      color #666
      line-height .54rem
      background #eee
      padding-left .2rem
      font-size .26rem
    .button-list
      overflow hidden
      padding .1rem .6rem .1rem .1rem
      .button-wrapper
        float left
        width 33.33%
        .button
          text-align center
          padding .1rem 0
          border-radius .06rem
          margin .1rem
          border .02rem solid #ccc
    .item-list
      .item
        line-height .76rem
        color #666
        padding-left .2rem
</style>
